Buggy code:
public class PictureController extends Tab implements Initializable { private static final int AVATAR_SIZE = 50 ; private static final int PICTURE_SIZE = 300 ; private final MainController app ; private Picture picture ; private ScrollPane ihm = new ScrollPane ( ) ; private VBox content = new VBox ( 8 ) ; private ImageView avatarImg = new ImageView ( ) ; private Text partageTxt = new Text ( ) ; private TextArea pictureName = new TextArea ( ) ; private Button refreshBtn = new Button ( "Refresh" ) ; private ImageView pictureImg = new ImageView ( ) ; private Text noteTitle = new Text ( "Note<seq2seq4repair_space>:<seq2seq4repair_space>" ) ; private HBox noteImg = new HBox ( ) ; private Text voteTxt = new Text ( ) ; private TextField voteField = new TextField ( "3" ) ; private Button voteBtn = new Button ( "Voter" ) ; private Text tagsTitle = new Text ( "Tags<seq2seq4repair_space>:<seq2seq4repair_space>" ) ; private Text tagsTxt = new Text ( ) ; private Text descTitle = new Text ( "Description<seq2seq4repair_space>:<seq2seq4repair_space>" ) ; private Text descTxt = new Text ( ) ; private Text comTitle = new Text ( "Commentaires<seq2seq4repair_space>:<seq2seq4repair_space>" ) ; private List < PictureController . CommentPane > comments = new ArrayList < PictureController . CommentPane > ( ) ; private TextArea writeArea = new TextArea ( ) ; private Button sendBtn = new Button ( "Envoyer" ) ; private Button descEditBtn = new Button ( "Modifier" ) ; private Button descDeleteBtn = new Button ( "Supprimer" ) ; private Button validateDescBtn = new Button ( "Terminer" ) ; private TextArea editDescTxt = new TextArea ( ) ; private Button tagsEditBtn = new Button ( "Terminer" ) ; private TextField tagsEditTxt = new TextField ( ) ; public PictureController ( Picture picture , MainController app ) { } public void build ( ) { } private void buildVotes ( ) { } private void buildTags ( ) { } private void addContent ( ) { } private void addCssClasses ( ) { ihm . getStyleClass ( ) . add ( "pic-ihm" ) ; ihm . setStyle ( "-fx-padding:<seq2seq4repair_space>20;" ) ; content . getStyleClass ( ) . add ( "pic-content" ) ; partageTxt . getStyleClass ( ) . add ( "pic-titles" ) ; noteTitle . getStyleClass ( ) . add ( "pic-titles" ) ; tagsTitle . getStyleClass ( ) . add ( "pic-titles" ) ; descTitle . getStyleClass ( ) . add ( "pic-titles" ) ; comTitle . getStyleClass ( ) . add ( "pic-titles" ) ; pictureName . getStyleClass ( ) . add ( "pic-title" ) ; pictureName . setStyle ( "-fx-background-insets:<seq2seq4repair_space>0px<seq2seq4repair_space>;" ) ; pictureName . setStyle ( ( "-fx-text-fill:<seq2seq4repair_space>black;" + ( ( ( ( "-fx-background-color:<seq2seq4repair_space>transparent;" + "-fx-font:<seq2seq4repair_space>Courier<seq2seq4repair_space>New;" ) + "-fx-font-family:<seq2seq4repair_space>Courier<seq2seq4repair_space>New;" ) + "-fx-font-weight:<seq2seq4repair_space>bold;" ) + "-fx-font-size:<seq2seq4repair_space>20;" ) ) ) ; } private void clearAndBuild ( ) { } public void receiveFullImage ( Picture picture ) { } private void comment ( MouseEvent mouseEvent ) { } private void vote ( MouseEvent mouseEvent ) { } private void editTags ( MouseEvent mouseEvent ) { } private void editDescription ( MouseEvent mouseEvent ) { } private void deleteComment ( PictureController . CommentPane cp ) { } private class CommentPane extends HBox { VBox vb = new VBox ( 5 ) ; public Comment comment ; public ImageView avatarImg = new ImageView ( ) ; public Text userTxt = new Text ( ) ; public Button editBtn = new Button ( "Editer" ) ; public Button delBtn = new Button ( "Supprimer" ) ; public Text commentTxt = new Text ( ) ; private TextField commentField = new TextField ( ) ; public CommentPane ( Comment comment ) { } public void build ( ) { } private void switchEditionMode ( boolean edition ) { } private void addContent ( ) { } private void addCssClasses ( ) { <START_BUG> userTxt . getStyleClass ( ) . add ( "pic-title" ) ; <END_BUG> } } private static void setImage ( ImageView img , Image source , int fitWidth , int fitHeight ) { } @ Override public void initialize ( final URL url , final ResourceBundle resourceBundle ) { } }

Fix:
userTxt . getStyleClass ( ) . add ( "pic-titles" ) ;